<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <meta http-equiv="X-UA-Compatible" content="ie=edge">
  <title>Document</title>
  <style>
    svg{
      border: 1px solid red;
      margin: 20px auto;
    }
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</head>
<body>
    <svg width="100" height="100" viewBox="50 50 50 50">
        <circle id="mycircle" cx="50" cy="50" r="50" />
      </svg>
</body>
</html>